Double glazed window



Dec. 15, 1936. F, GELSTHARP ET AL 2,064,530

' DOUBLE GLAZED WINDOW Filedl March 21, 1934 1w *f ""l' "11 Patented Dec. l5, 1936 UNITED STATES 2,064,530 DOUBLEv GLAzED WINDOW Frederick Gelstharp and Joseph Carl Parkinson, Tarentum, Pa., assignors to Pittsburgh Plate Glass Company, a corporation of Pennsylvania Application March 21, 1934, Serial No. 716,636

2 Claims.

' The invention relates to a double glazed window construction for use in buildings and refrigerator c'ase structures. It has for its principal objects, (l) the provision of improved means for hermetically sealing off the space between the glass sheets from the outer atmosphere; (2) the provision of a construction applicable to ordinary wood sash which permits the Vready removal of the sheets for cleaning or replacement; and 3) the provision of a construction having improved means permitting the filling of the space between the glass sheets with dry air in order to avoid condensation and prevent or limit the formation of an alkaline clouding film on the vinner surfaces of the sheets. Certain embodiments of the invention are illustratedin the accompanying drawing, wherein:

Figure 1 is a front elevation of the construction. Fig. 2 is a section on the line II-II of Fig. 3 .is a detail perspective view of the sealing member. Fig. 4 is a detail view partially in section of 'the sealing member. And Figs. 5 and 6 are sectional views illustrating modifications. Referring to the construction of Figs. 1 to 4, lis a sash which is in this instance of wood; 2, 2 are sheets of glass; 3 is a packing or sealing member placed between the glass sheets; and il is a clamping plate which engages the outer face 30 of one of the glass sheets, such plate being held in place by the screws 5 and being of wood in the present instance. The sash l is provided with a Seating abutment or shoulder 6 whose outer portions act as seating ledges for the edges of the glass sheets and is also provided with a shoulder 'l in opposition to the outer face of one of the glass sheets 2.

The sealing member is preferably in the form of an integral rectangular frame of metal which 40 ts vsnugly into the sash andis provided on `its opposite faces with the rubber sealing strips 3 and '9 which are preferably cemented to the member 3. `When the parts are positioned, as indicated in Figs. 1 and 2, and theplate 4 is clamped in position by means of thescrews 5, the rubber strips 8 and 9 are placed under compression so v that they are thinned and widened, as indicated in Fig. "2, and form a very secure seal/for the space between the two glass sheets. f vIn order to provide for the application of dry air to the space between the sheets 2, 2, the tubes I0, l0 are provided, such tubes extending through the sash and through the member 3, as indicated in Figs.j2 and 4, the inner ends ofthe tubes being screwed into the member 3 so that they are se- (Cl. 2li-56.5)

curely held in position and'act as an anchoring means for the member 3. In order to prevent condensation, and elorescence upon the inner ,suitable means whereby dry air is forced through one of the tubes I0, and is evacuated through the other tubes until the air which fills the space between the glass sheets is completely dry. The .10l outer ends of .the tubes are then sealed by means of the screws Il, li which are threaded into Ithe tubes.

Fig. 5 illustrates a modification in which the sash i2 is of metal instead of wood and in which 15 two clamping plates i3', I3 are employed, such plates being held in place by means of the machine screws I4. In this instance, the transparent plates l5, l5 are of safety glass; that is, each plate consists of a pair `of sheets of thin 2U plate glass with an interposed sheet of reinforcing vmaterial to which the glass sheets are cemented. In this construction,the sealing member I6 is integral with the sash instead of being separate therefrom and is provided on its sides 25 with sealing strips of rubber, similar to the strips 8 and 9 heretofore described.

Fig. 6 illustrates another modification in which the sash I'l is of metal and the glass sheets I8, I8 are held in position by means of the single metal plate i9 secured by the screws 20. In this case, the sealing member 2l is of the same construction as in Figs. 1 to 4.

When safety glass is used in the construction, as shown in Fig. 5, it is highly desirable that 35 a special form of such glass be used, in order that the transparency of the window shall be unimpaired after a long period of service. The

,cellulose plastic reinforcing between the sheets tends to become yellow and brittle in the course 40 of time, due to the decomposing action of ultral violet light, and in order to counteract this tendency, the outer glass sheet of each pane is made with a small content of an oxide, such as iron oxide, which acts as an ultraviolet ray cut-01T 45 medium. An amount of from .35 to 1.00 per cent of iron oxide serves to cut 01T the major portion of the damaging ultraviolet rays, and at the same time, adds only a slight tinge of color to the glass. The inner sheet of each 50 l pane of glass is also vpreferably` made from a special batch in order to avoid the phenomenon known as elorescence. 'I'his is a deposit of white alkaline dust which occurs upon glass and becomes noticeable in a double glazed structure 55 because the inner surfaces of the glass sheets are not accessible for wiping. With dry air in the insulating space, this deposit'is reduced to a minimum, but in order to further guard against this defect, the inner sheets of glass are made from a batch containing from 2 to 10 percent of potassium oxide. This has been found to reduce elorescence to a negligible amount. The window, as thus constructed, therefore maintains its original appearance through a period of service in .which a window employing ordinary safety glass would become so discolored and clouded as to require replacement. Oxides other than iron oxide may be used in the glass as ultraviolet cut-off ingredients, such as cerium, titanium, nickel, and chromium, and both the inner and outer sheets may have a content of both iron oxide or its equivalent, and potassium oxide, but this involves much greater cost with no added advantage. l

What we claim is z 1. In combination with a sash having seating ledges for the glass sheets with surfaces for engaging the edges of the sheets extending at right angles to the plane of such sheets, a pair of parallel glass sheets in the 'sash a pair of into the strip at their inner ends, and closure means for the tubes.

2. A non-condensing glazing panel comprising va spacer frame composed of rails of relatively non-compressib1e material secured rigidly together at their junctures, strips of flexible elastic material carried by and extending from the lateral faces of said rails, plates of glass sealed to said respective strips of elastic material, and an anhydrous fluid provided between said plates of glass.

FREDERICK GELSTHARP.

JOSEPH CARL PARKINSON. 25 

